No one has become ill since December and all potentially affected lettuce is off the shelves now, the Centers for Disease Control and Prevention said. In all, 62 people got sick in the U.S. and 29 in Canada.

“This outbreak appears to be over as of January 9, 2019,” the CDC said in a statement. It said 25 were ill enough to be hospitalized, although no one has died.

The outbreak was traced to farms in California, and so far, one farm in particular was found to have E. coli with the same DNA fingerprint. “CDC identified the outbreak strain of E. coli 0157:H7 in sediment collected within an agricultural water reservoir on an Adam Bros. Farming Inc. farm in Santa Barbara County, which was identified in the traceback investigation,” the agency said.

But officials said one farm could not have been the source of all the contamination. The Food and Drug Administration said it was continuing its investigation.

While food safety inspections have virtually stopped because of the government shutdown, the FDA says active investigations are continuing.

The outbreak was one of two linked to romaine lettuce last year. An outbreak in the spring was linked to romaine lettuce grown in Arizona.

Foodborne illnesses are very common. The CDC estimates that 48 million Americans get sick from a foodborne illness every year. Among them, 128,000 are hospitalized, and 3,000 die.